The present disclosure generally relates to an aircraft control surface operating device, and more particularly relates to an aircraft control surface operating device which incorporates at least one bearing joint.
Aircrafts may be provided with control surfaces which are operable to modify an aerodynamic profile of the aircraft. Generally, the control surfaces may be provided on any portion of an aircraft body and are movable between different positions, each of which modify the aerodynamic profile of the aircraft in a particular manner. The modified aerodynamic profile provided by the control surfaces may be used to facilitate desired aircraft maneuvers, such as taking-off, landing, ascending, descending, turning, etc.
One example of an aircraft control surface used in a winged aircraft is a wing flap. Wing flaps may be hinged surfaces provided on a trailing edge of aircraft wings. The wing flaps may be extended and retracted to modify the aerodynamic profile of the aircraft in a desired manner. Particularly, extending the flaps increases a camber of the aircraft wings, and therefore raises a maximum lift coefficient. The increase in the maximum lift coefficient allows the aircraft to generate a necessary/desired lift while flying at a lower speed, thereby reducing a stalling speed of the aircraft. Accordingly, the aircraft may safely fly at lower speeds, such as may be required during take-off and landing. Extending the wing flaps also increases drag on the aircraft, which can be beneficial during landing and approach for landing as the drag helps to slow down the aircraft. Conversely, during flight it may be desirable to reduce drag on the aircraft to allow for increased aircraft speed. As such, the wing flaps may be retracted during flight.
The control surfaces may be controlled by operating devices which move the control surfaces between the possible positions. For example, in an exemplary wing flap, a wing flap operating device may be provided to move the wing flap between the extended and retracted positions. The operating device(s) may be connected to and controlled by a pilot control system within the aircraft, such as in the aircraft cockpit. A control surface operating device is described in U.S. Pat. No. 6,464,176, the contents of which are hereby incorporated in full by reference.
As aircrafts may travel at high speeds during flight, it is to be appreciated that the control surfaces may be subjected to significant forces caused by the airflow contacting the control surfaces (as well as other forces, such as gravity, etc.). As the control surface operating devices may be connected to the associated control surfaces, the operating devices may similarly be subjected to these forces. Accordingly, the operating devices may benefit from a configuration suited to handle these forces. Additionally, the operating devices may be bulky or require redesign of other aircraft components, often to the detriment of another aircraft feature. As such, a compact control surface operating device may be beneficial.